Please consider adding PyPy Trove classifiers, because apparently black works fine! At least on the recent PyPy (I tested PyPy3.6 v7.0 on macOS). I used version 18.9b0 of black. See https://pypy.org/download.html

test_merged_config() in confi.rs creates and uses folder name a, usually under /tmp directory. The problem is that /tmp/a is a commonly used for other purposes, and that can cause problems as happened to me in #4400. It would be better if a more rust unique name will be used instead of "a".

When I try to beautify the i get the following problem
TypeError: Cannot read property 'on' of undefined

I just installed beautify and uncrustify

https://gist.github.com/ODCA117/917affd6b11437517535a45350379820

I really don't know if we have some rules to create Mercosul/Brazilian license plate, but I think that we should keep support for both (after 2024 we can drop Brazilian support since Brazil will only use Mercosul format).